Is there a seamless DEM product available for the lower 48 states in 1 Arc Second (30m) resolution? Thanks
The NED (National Elevation Dataset) may be what you're looking for - http://viewer.nationalmap.gov/basic/?basemap=b1&category=ned,nedsrc&title=3DEP%20View
Further Robert's link, there is more information here The National Map: Elevation
Retrieving data ...